I think what he means is download the latest version of DOSbox (0.74) and replace the old DOSbox files (0.72) in your Ultimate Doom/base folder with the new ones. I had the color issue and this worked for me.

I think what he means is download the latest version of DOSbox (0.74) and replace the old DOSbox files (0.72) in your Ultimate Doom/base folder with the new ones. I had the color issue and this worked for me.

When launching a DOS game from Steam, it will automatically launch DOSBox for the game. Since DOOM on Steam apparently comes with an old version of DOSBox, downloading the latest 0.74 DOSBox version and using that to run the game, might fix some issues.